the enormity of the challenge
climate change has implications for economic growth, human security and social wellbeing, especially for the poorest and most marginalised people. how countries cope with climate change will depend on wealth, poverty leads to poor health, malnutrition and an inability to cope with extreme weather events
there is a vicious cycle of problems generated by climate change:
higher temperatures (more hazardous world, great impact on water and food supplies)
lead to increased evaporation (more water vapour, more ice sheets melting, accelerating changes due to positive feedback)
leads to worsening greenhouse effect (major issue is rising sea levels, global warming impacts)
leads to more uncertainty (more extreme weather with more uncertainty - changes in precipitation patterns, growing incidence of floods and severe storms)
leads to more impacts (more food insecurity, conflicts over water insecurity, more vunerable people, environmental refugees)
(the cycle repeats itself)
as population increases so do the demand on water supplies, for agriculture and indusry, estimates suggests that water demand could rise by 50%. The world bank estimates that as much as 50% of the worlds populations (concentrated in Africa) will face water shortages by 2025.
Currently 1.2 billion experience stress because of physical scarcity, 1.6 billion experience economic water scarcity because of poverty and poor governance.
The problem is made worse by climate issues; high temperatures in cities, unreliable supplies of rain, dissaperance of glaciers (e.g himalayas) private companies in some countries have been allowed to provide water to large cities, disasterous for the urban poor.
Water stresses can lead to conflicts; Egypt relies heavily on the river Nile for its water supply, but it is an internationally owned river, Egpyt build a dam which created a large lake to store water, in 1980's Sudan and Ethiopia suffered droughts that lead to famine, Egypt wasnt affected because it had enough water stored in lake Nasser
Food security means that populations have access to enough food for an active and healthy life, food insecurity results from lack of available food because of physical factors like climate or when food is available a communit or individual is too poor to access it.
- Higher temperatures stress crops and reduce yields, yet prolong growing seasons allowing a wider range of crops to be grown
- Higher temperatures can promote the growth of crop pests and diseases
- Higher concentration of CO2 speeds plant growth and increases resilience to water stress, favourable in some areas up until a certain point (midwest USA)
- Certain areas (east Africa) will have more rainfall
In theory agriculture is adapatable, there are many techniques to overcome water stress and therefore food insecurity but these techniques can not be adopted by many as they require money and skills. Vital food crops (rice, wheat and corn) could plummet by over a third in the next 20 years